Switching power supply device, and inverter, converter, air conditioner, solar power controller, and automobile employing same

Patent metadata

Field	Value
Publication number	US-9831756-B2
Application number	US-201213610417-A
Country	US
Kind code	B2
Filing date	Sep 11, 2012
Priority date	Sep 30, 2011
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

The switching power supply device is provided with a high-withstand voltage first transistor, a first electrode of which being connected to a first node; a low-withstand voltage second transistor, a first electrode of which being connected to a second electrode of the first transistor, and a second electrode of which being connected to a second node; and a drive circuit. Each of the first and second transistors has a parasitic diode connected in the forward direction between the second and first electrodes. The drive circuit, in a case where electrical current is to flow from the first node to the second node, turns on the first and second transistors, and, in a case where electrical current is to flow from the second node to the first node, turns on the first transistor, and turns off the second transistor.

First claim

What is claimed is:

1. A switching power supply device, comprising:
a first transistor, a first electrode of which being connected to a first node;
a second transistor, a first electrode of which being connected to a second electrode of the first transistor, and a second electrode of which being connected to a second node; and
a drive circuit;
wherein each of the first and second transistors has a parasitic diode connected in the forward direction between the second and first electrodes;
wherein the withstand voltage between the first and second electrodes of the first transistor is higher than the withstand voltage between the first and second electrodes of the second transistor;
wherein the drive circuit, in a case where electrical current is to flow from the first node to the second node, turns on the first and second transistors, and in a case where electrical current is to flow from the second node to the first node, turns on the first transistor, and turns off the second transistor, and
wherein the drive circuit supplies a control electrode of the first transistor with a voltage that is higher than a voltage obtained by adding a threshold voltage of the first transistor to the voltage of the second node so as to turn on the first transistor.

2. The switching power supply device of claim 1 ,
the drive circuit including:
a capacitor connected between the control electrode of the first transistor and the second node; and
a diode, a cathode of which being connected to the control electrode of the first transistor, and an anode of which receiving a voltage greater than the threshold voltage of the first transistor.

3. The switching power supply device of claim 1 ,
the drive circuit turning on the first transistor when the switching power supply device is operated, and turning off the first transistor when the switching power supply device is idle.

4. The switching power supply device of claim 3 ,
the drive circuit including:
a capacitor connected between the control electrode of the first transistor and the second node;
a diode, the cathode of which being connected to the control electrode of the first transistor; and
a third transistor, a first electrode of which receives a voltage greater than the threshold voltage of the first transistor, and a second electrode of which being connected to the anode of the diode; and
the drive circuit, when the switching power supply device is operated, turning on the third transistor and turning on the first transistor; and, when the switching power supply device is idle, turning off the third transistor and turning off the first transistor.

5. The switching power supply device of claim 1 , further provided with
a coil for accumulating and discharging electromagnetic energy,
one terminal of the coil being connected to the first or second node.

6. The switching power supply device of claim 1 , further provided with
a transformer that includes primary and secondary windings,
one terminal of the primary winding being connected to the first or second node.

7. The switching power supply device of claim 1 , further provided with
a zener diode, an anode of which being connected to the second electrode of the second transistor, and a cathode of which being connected to the first electrode of the second transistor.

8. A converter adapted to step up or step down DC voltage, provided with the switching power supply device of claim 1 .

9. An inverter adapted to convert DC voltage to AC voltage, provided with the switching power supply device of claim 1 .

10. An air conditioner, provided with the switching power supply device of claim 1 .

11. A solar power controller, provided with the switching power supply device of claim 1 .

12. An automobile, provided with the switching power supply device of claim 1 .

13. The switching power supply device of claim 1 , wherein the first transistor is an enhancement transistor.

14. A switching power supply device, comprising:
a first transistor, a first electrode of which being connected to a first node;
a second transistor, a first electrode of which being connected to a second electrode of the first transistor, and a second electrode of which being connected to a second node; and
a drive circuit;
wherein each of the first and second transistors has a parasitic diode connected in the forward direction between the second and first electrodes;
wherein the withstand voltage between the first and second electrodes of the first transistor is higher than the withstand voltage between the first and second electrodes of the second transistor;
wherein the drive circuit, in a case where electrical current is to flow from the first node to the second node, turns on the first and second transistors, and in a case where electrical current is to flow from the second node to the first node, turns on the first transistor, turns on the second transistor when electrical current has begun to flow from the second node to the first node, and turns off the second transistor before electrical current ceases to flow from the second node to the first node, and
wherein the drive circuit supplies a control electrode of the first transistor with a voltage that is higher than a voltage obtained by adding a threshold voltage of the first transistor to the voltage of the second node so as to turn on the first transistor.

15. A converter adapted to step up or step down DC voltage, provided with the switching power supply device of claim 14 .

16. An inverter adapted to convert DC voltage to AC voltage, provided with the switching power supply device of claim 14 .

17. The switching power supply device of claim 14 , wherein the first transistor is an enhancement transistor.

18. A switching power supply device, comprising:
a first transistor, a first electrode of which being connected to a power supply voltage line;
a second transistor, a first electrode of which being connected to a second electrode of the first transistor, and a second electrode of which being connected to an output node;
a third transistor, a first electrode of which being connected to the output node;
a fourth transistor, a first electrode of which being connected to a second electrode of the third transistor, and a second electrode of which being connected to a reference voltage line; and
a drive circuit;
wherein each of the first to fourth transistors has a parasitic diode connected in the forward direction between the second and first electrodes;
wherein the withstand voltage between the first and second electrodes of the first transistor is higher than the withstand voltage between the first and second electrodes of the second transistor;
wherein the withstand voltage between the first and second electrodes of the third transistor is higher than the withstand voltage between the first and second electrodes of the fourth transistor;
wherein the drive circuit, in a case where electrical current is to flow from the power supply voltage line to the output node, turns on the first and second transistors, in a case where electrical current is to flow from the output node to the power supply voltage line, turns on the first transistor, and turns off the second transistor, in a case where electrical current is to flow from the output node to the reference voltage line, turns on the third and fourth transistors, and in a case where electrical current is to flow from the reference voltage line to the output node, turns on the third transistor, and turns off the fourth transistor, and
the drive circuit supplies a c

Assignees

• Komiya Kenji
• Wakaiki Shuji
• Shibata Akihide
• Iwata Hiroshi
• Sharp Kk

Inventors

• Komiya Kenji
• Wakaiki Shuji
• Shibata Akihide
• Iwata Hiroshi

Classifications

• H02M3/1582

  Buck-boost converters (H02M3/1584 takes precedence) · CPC title

• Y02B70/1466

  Cross-Sectional Technologies · mapped topic

• H02M7/5387 Primary

  in a bridge configuration · CPC title

• Y02T10/7258

  Cross-Sectional Technologies · mapped topic

• H02M2001/0051

  Electricity · mapped topic